At the end of the 10th century, Genghis Khan (Temujin)' s brother Duvasuoer had four sons, namely, the eldest son Tonoy, the second son Dokus, the third son Ernik and the fourth son Hongxing Erke. After the death of their father Duwa Sochor, they left Wonan River (now Nenjiang River in Mongolia) and moved eastward, returning to Hulunbeier, the birthplace of Mongols, and called Duer Bian Shi. Dolby is also called Dolby Bing, Dolby Ban, Dolibo, Bald without Belt, Dolbert, etc. /kloc-in the 0/2nd century, Dulbert gradually moved eastward to Nenjiang River and Tongken River.

In A.D. 1547 (the 26th year of Ming Jiajing), after the death of Chikhan, the 17th Khan of Northern Yuan Dynasty, his son Da Lai Sun Kudenghan succeeded to the throne. In order to avoid the threat of Mongolian right-wing forces, D 'Alesun Kuden Khan led his troops eastward. At this time, Kuimengketashala, the 14th grandson of Hasal who lived in Hulunbeier grassland, moved from Hulunbeier grassland to the east of Daxing 'anling, and began to call his tribe the tender (agricultural) Horqin Department. Divided into four sides and ten flags, left and right wings. The four departments are Horqin Department, Zhalaite Department, Guoerluosi Department and Dulbert Department. The ten banners are Horqin right-wing front banner, Horqin right-wing middle banner, Horqin right-wing back banner, right-wing Zalaite banner and right-wing Dorbert banner; Horqin Left Front Banner, Horqin Left Middle Banner, Horqin Left Rear Banner, Guoerluosi Left Front Banner and Guoerluosi Left Rear Banner. The first five flags are right-wing and the last five flags are left-wing. At that time, Dolbert was grazing in some areas on the left bank of the middle reaches of Nenjiang River, facing Zhalaite Banner across the river.